ffmpeg/libavformat/hlsenc.c

664 lines
22 KiB
C

/*
* Apple HTTP Live Streaming segmenter
* Copyright (c) 2012, Luca Barbato
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include <float.h>
#include <stdint.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include "libavutil/avassert.h"
#include "libavutil/mathematics.h"
#include "libavutil/parseutils.h"
#include "libavutil/avstring.h"
#include "libavutil/opt.h"
#include "libavutil/log.h"
#include "avformat.h"
#include "internal.h"
#include "os_support.h"
#define KEYSIZE 16
#define LINE_BUFFER_SIZE 1024
typedef struct HLSSegment {
char filename[1024];
double duration; /* in seconds */
int64_t pos;
int64_t size;
char key_uri[LINE_BUFFER_SIZE + 1];
char iv_string[KEYSIZE*2 + 1];
struct HLSSegment *next;
} HLSSegment;
typedef enum HLSFlags {
// Generate a single media file and use byte ranges in the playlist.
HLS_SINGLE_FILE = (1 << 0),
HLS_DELETE_SEGMENTS = (1 << 1),
HLS_ROUND_DURATIONS = (1 << 2),
HLS_DISCONT_START = (1 << 3),
HLS_OMIT_ENDLIST = (1 << 4),
} HLSFlags;
typedef struct HLSContext {
const AVClass *class; // Class for private options.
unsigned number;
int64_t sequence;
int64_t start_sequence;
AVOutputFormat *oformat;
AVFormatContext *avf;
float time; // Set by a private option.
int max_nb_segments; // Set by a private option.
int wrap; // Set by a private option.
uint32_t flags; // enum HLSFlags
char *segment_filename;
int allowcache;
int64_t recording_time;
int has_video;
int64_t start_pts;
int64_t end_pts;
double duration; // last segment duration computed so far, in seconds
int64_t start_pos; // last segment starting position
int64_t size; // last segment size
int nb_entries;
int discontinuity_set;
HLSSegment *segments;
HLSSegment *last_segment;
HLSSegment *old_segments;
char *basename;
char *baseurl;
char *format_options_str;
AVDictionary *format_options;
char *key_info_file;
char key_file[LINE_BUFFER_SIZE + 1];
char key_uri[LINE_BUFFER_SIZE + 1];
char key_string[KEYSIZE*2 + 1];
char iv_string[KEYSIZE*2 + 1];
} HLSContext;
static int hls_delete_old_segments(HLSContext *hls) {
HLSSegment *segment, *previous_segment = NULL;
float playlist_duration = 0.0f;
int ret = 0, path_size;
char *dirname = NULL, *p, *path;
segment = hls->segments;
while (segment) {
playlist_duration += segment->duration;
segment = segment->next;
}
segment = hls->old_segments;
while (segment) {
playlist_duration -= segment->duration;
previous_segment = segment;
segment = previous_segment->next;
if (playlist_duration <= -previous_segment->duration) {
previous_segment->next = NULL;
break;
}
}
if (segment) {
if (hls->segment_filename) {
dirname = av_strdup(hls->segment_filename);
} else {
dirname = av_strdup(hls->avf->filename);
}
if (!dirname) {
ret = AVERROR(ENOMEM);
goto fail;
}
p = (char *)av_basename(dirname);
*p = '\0';
}
while (segment) {
av_log(hls, AV_LOG_DEBUG, "deleting old segment %s\n",
segment->filename);
path_size = strlen(dirname) + strlen(segment->filename) + 1;
path = av_malloc(path_size);
if (!path) {
ret = AVERROR(ENOMEM);
goto fail;
}
av_strlcpy(path, dirname, path_size);
av_strlcat(path, segment->filename, path_size);
if (unlink(path) < 0) {
av_log(hls, AV_LOG_ERROR, "failed to delete old segment %s: %s\n",
path, strerror(errno));
}
av_free(path);
previous_segment = segment;
segment = previous_segment->next;
av_free(previous_segment);
}
fail:
av_free(dirname);
return ret;
}
static int hls_encryption_start(AVFormatContext *s)
{
HLSContext *hls = s->priv_data;
int ret;
AVIOContext *pb;
uint8_t key[KEYSIZE];
if ((ret = avio_open2(&pb, hls->key_info_file, AVIO_FLAG_READ,
&s->interrupt_callback, NULL)) < 0) {
av_log(hls, AV_LOG_ERROR,
"error opening key info file %s\n", hls->key_info_file);
return ret;
}
ff_get_line(pb, hls->key_uri, sizeof(hls->key_uri));
hls->key_uri[strcspn(hls->key_uri, "\r\n")] = '\0';
ff_get_line(pb, hls->key_file, sizeof(hls->key_file));
hls->key_file[strcspn(hls->key_file, "\r\n")] = '\0';
ff_get_line(pb, hls->iv_string, sizeof(hls->iv_string));
hls->iv_string[strcspn(hls->iv_string, "\r\n")] = '\0';
avio_close(pb);
if (!*hls->key_uri) {
av_log(hls, AV_LOG_ERROR, "no key URI specified in key info file\n");
return AVERROR(EINVAL);
}
if (!*hls->key_file) {
av_log(hls, AV_LOG_ERROR, "no key file specified in key info file\n");
return AVERROR(EINVAL);
}
if ((ret = avio_open2(&pb, hls->key_file, AVIO_FLAG_READ,
&s->interrupt_callback, NULL)) < 0) {
av_log(hls, AV_LOG_ERROR, "error opening key file %s\n", hls->key_file);
return ret;
}
ret = avio_read(pb, key, sizeof(key));
avio_close(pb);
if (ret != sizeof(key)) {
av_log(hls, AV_LOG_ERROR, "error reading key file %s\n", hls->key_file);
if (ret >= 0 || ret == AVERROR_EOF)
ret = AVERROR(EINVAL);
return ret;
}
ff_data_to_hex(hls->key_string, key, sizeof(key), 0);
return 0;
}
static int hls_mux_init(AVFormatContext *s)
{
HLSContext *hls = s->priv_data;
AVFormatContext *oc;
int i, ret;
ret = avformat_alloc_output_context2(&hls->avf, hls->oformat, NULL, NULL);
if (ret < 0)
return ret;
oc = hls->avf;
oc->oformat = hls->oformat;
oc->interrupt_callback = s->interrupt_callback;
oc->max_delay = s->max_delay;
av_dict_copy(&oc->metadata, s->metadata, 0);
for (i = 0; i < s->nb_streams; i++) {
AVStream *st;
if (!(st = avformat_new_stream(oc, NULL)))
return AVERROR(ENOMEM);
avcodec_copy_context(st->codec, s->streams[i]->codec);
st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
st->time_base = s->streams[i]->time_base;
}
hls->start_pos = 0;
return 0;
}
/* Create a new segment and append it to the segment list */
static int hls_append_segment(HLSContext *hls, double duration, int64_t pos,
int64_t size)
{
HLSSegment *en = av_malloc(sizeof(*en));
int ret;
if (!en)
return AVERROR(ENOMEM);
av_strlcpy(en->filename, av_basename(hls->avf->filename), sizeof(en->filename));
en->duration = duration;
en->pos = pos;
en->size = size;
en->next = NULL;
if (hls->key_info_file) {
av_strlcpy(en->key_uri, hls->key_uri, sizeof(en->key_uri));
av_strlcpy(en->iv_string, hls->iv_string, sizeof(en->iv_string));
}
if (!hls->segments)
hls->segments = en;
else
hls->last_segment->next = en;
hls->last_segment = en;
if (hls->max_nb_segments && hls->nb_entries >= hls->max_nb_segments) {
en = hls->segments;
hls->segments = en->next;
if (en && hls->flags & HLS_DELETE_SEGMENTS &&
!(hls->flags & HLS_SINGLE_FILE || hls->wrap)) {
en->next = hls->old_segments;
hls->old_segments = en;
if ((ret = hls_delete_old_segments(hls)) < 0)
return ret;
} else
av_free(en);
} else
hls->nb_entries++;
hls->sequence++;
return 0;
}
static void hls_free_segments(HLSSegment *p)
{
HLSSegment *en;
while(p) {
en = p;
p = p->next;
av_free(en);
}
}
static int hls_window(AVFormatContext *s, int last)
{
HLSContext *hls = s->priv_data;
HLSSegment *en;
int target_duration = 0;
int ret = 0;
AVIOContext *out = NULL;
char temp_filename[1024];
int64_t sequence = FFMAX(hls->start_sequence, hls->sequence - hls->nb_entries);
int version = hls->flags & HLS_SINGLE_FILE ? 4 : 3;
const char *proto = avio_find_protocol_name(s->filename);
int use_rename = proto && !strcmp(proto, "file");
static unsigned warned_non_file;
char *key_uri = NULL;
char *iv_string = NULL;
if (!use_rename && !warned_non_file++)
av_log(s, AV_LOG_ERROR, "Cannot use rename on non file protocol, this may lead to races and temporarly partial files\n");
snprintf(temp_filename, sizeof(temp_filename), use_rename ? "%s.tmp" : "%s", s->filename);
if ((ret = avio_open2(&out, temp_filename, AVIO_FLAG_WRITE,
&s->interrupt_callback, NULL)) < 0)
goto fail;
for (en = hls->segments; en; en = en->next) {
if (target_duration < en->duration)
target_duration = ceil(en->duration);
}
hls->discontinuity_set = 0;
avio_printf(out, "#EXTM3U\n");
avio_printf(out, "#EXT-X-VERSION:%d\n", version);
if (hls->allowcache == 0 || hls->allowcache == 1) {
avio_printf(out, "#EXT-X-ALLOW-CACHE:%s\n", hls->allowcache == 0 ? "NO" : "YES");
}
avio_printf(out, "#EXT-X-TARGETDURATION:%d\n", target_duration);
avio_printf(out, "#EXT-X-MEDIA-SEQUENCE:%"PRId64"\n", sequence);
av_log(s, AV_LOG_VERBOSE, "EXT-X-MEDIA-SEQUENCE:%"PRId64"\n",
sequence);
if((hls->flags & HLS_DISCONT_START) && sequence==hls->start_sequence && hls->discontinuity_set==0 ){
avio_printf(out, "#EXT-X-DISCONTINUITY\n");
hls->discontinuity_set = 1;
}
for (en = hls->segments; en; en = en->next) {
if (hls->key_info_file && (!key_uri || strcmp(en->key_uri, key_uri) ||
av_strcasecmp(en->iv_string, iv_string))) {
avio_printf(out, "#EXT-X-KEY:METHOD=AES-128,URI=\"%s\"", en->key_uri);
if (*en->iv_string)
avio_printf(out, ",IV=0x%s", en->iv_string);
avio_printf(out, "\n");
key_uri = en->key_uri;
iv_string = en->iv_string;
}
if (hls->flags & HLS_ROUND_DURATIONS)
avio_printf(out, "#EXTINF:%d,\n", (int)round(en->duration));
else
avio_printf(out, "#EXTINF:%f,\n", en->duration);
if (hls->flags & HLS_SINGLE_FILE)
avio_printf(out, "#EXT-X-BYTERANGE:%"PRIi64"@%"PRIi64"\n",
en->size, en->pos);
if (hls->baseurl)
avio_printf(out, "%s", hls->baseurl);
avio_printf(out, "%s\n", en->filename);
}
if (last && (hls->flags & HLS_OMIT_ENDLIST)==0)
avio_printf(out, "#EXT-X-ENDLIST\n");
fail:
avio_closep(&out);
if (ret >= 0 && use_rename)
ff_rename(temp_filename, s->filename, s);
return ret;
}
static int hls_start(AVFormatContext *s)
{
HLSContext *c = s->priv_data;
AVFormatContext *oc = c->avf;
AVDictionary *options = NULL;
char *filename, iv_string[KEYSIZE*2 + 1];
int err = 0;
if (c->flags & HLS_SINGLE_FILE)
av_strlcpy(oc->filename, c->basename,
sizeof(oc->filename));
else
if (av_get_frame_filename(oc->filename, sizeof(oc->filename),
c->basename, c->wrap ? c->sequence % c->wrap : c->sequence) < 0) {
av_log(oc, AV_LOG_ERROR, "Invalid segment filename template '%s'\n", c->basename);
return AVERROR(EINVAL);
}
c->number++;
if (c->key_info_file) {
if ((err = hls_encryption_start(s)) < 0)
return err;
if ((err = av_dict_set(&options, "encryption_key", c->key_string, 0))
< 0)
return err;
err = av_strlcpy(iv_string, c->iv_string, sizeof(iv_string));
if (!err)
snprintf(iv_string, sizeof(iv_string), "%032"PRIx64, c->sequence);
if ((err = av_dict_set(&options, "encryption_iv", iv_string, 0)) < 0)
return err;
filename = av_asprintf("crypto:%s", oc->filename);
if (!filename) {
av_dict_free(&options);
return AVERROR(ENOMEM);
}
err = avio_open2(&oc->pb, filename, AVIO_FLAG_WRITE,
&s->interrupt_callback, &options);
av_free(filename);
av_dict_free(&options);
if (err < 0)
return err;
} else
if ((err = avio_open2(&oc->pb, oc->filename, AVIO_FLAG_WRITE,
&s->interrupt_callback, NULL)) < 0)
return err;
if (oc->oformat->priv_class && oc->priv_data)
av_opt_set(oc->priv_data, "mpegts_flags", "resend_headers", 0);
return 0;
}
static int hls_write_header(AVFormatContext *s)
{
HLSContext *hls = s->priv_data;
int ret, i;
char *p;
const char *pattern = "%d.ts";
AVDictionary *options = NULL;
int basename_size;
hls->sequence = hls->start_sequence;
hls->recording_time = hls->time * AV_TIME_BASE;
hls->start_pts = AV_NOPTS_VALUE;
if (hls->format_options_str) {
ret = av_dict_parse_string(&hls->format_options, hls->format_options_str, "=", ":", 0);
if (ret < 0) {
av_log(s, AV_LOG_ERROR, "Could not parse format options list '%s'\n", hls->format_options_str);
goto fail;
}
}
for (i = 0; i < s->nb_streams; i++)
hls->has_video +=
s->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO;
if (hls->has_video > 1)
av_log(s, AV_LOG_WARNING,
"More than a single video stream present, "
"expect issues decoding it.\n");
hls->oformat = av_guess_format("mpegts", NULL, NULL);
if (!hls->oformat) {
ret = AVERROR_MUXER_NOT_FOUND;
goto fail;
}
if (hls->segment_filename) {
hls->basename = av_strdup(hls->segment_filename);
if (!hls->basename) {
ret = AVERROR(ENOMEM);
goto fail;
}
} else {
if (hls->flags & HLS_SINGLE_FILE)
pattern = ".ts";
basename_size = strlen(s->filename) + strlen(pattern) + 1;
hls->basename = av_malloc(basename_size);
if (!hls->basename) {
ret = AVERROR(ENOMEM);
goto fail;
}
av_strlcpy(hls->basename, s->filename, basename_size);
p = strrchr(hls->basename, '.');
if (p)
*p = '\0';
av_strlcat(hls->basename, pattern, basename_size);
}
if ((ret = hls_mux_init(s)) < 0)
goto fail;
if ((ret = hls_start(s)) < 0)
goto fail;
av_dict_copy(&options, hls->format_options, 0);
ret = avformat_write_header(hls->avf, &options);
if (av_dict_count(options)) {
av_log(s, AV_LOG_ERROR, "Some of provided format options in '%s' are not recognized\n", hls->format_options_str);
ret = AVERROR(EINVAL);
goto fail;
}
av_assert0(s->nb_streams == hls->avf->nb_streams);
for (i = 0; i < s->nb_streams; i++) {
AVStream *inner_st = hls->avf->streams[i];
AVStream *outer_st = s->streams[i];
avpriv_set_pts_info(outer_st, inner_st->pts_wrap_bits, inner_st->time_base.num, inner_st->time_base.den);
}
fail:
av_dict_free(&options);
if (ret < 0) {
av_freep(&hls->basename);
if (hls->avf)
avformat_free_context(hls->avf);
}
return ret;
}
static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
{
HLSContext *hls = s->priv_data;
AVFormatContext *oc = hls->avf;
AVStream *st = s->streams[pkt->stream_index];
int64_t end_pts = hls->recording_time * hls->number;
int is_ref_pkt = 1;
int ret, can_split = 1;
if (hls->start_pts == AV_NOPTS_VALUE) {
hls->start_pts = pkt->pts;
hls->end_pts = pkt->pts;
}
if (hls->has_video) {
can_split = st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
pkt->flags & AV_PKT_FLAG_KEY;
is_ref_pkt = st->codec->codec_type == AVMEDIA_TYPE_VIDEO;
}
if (pkt->pts == AV_NOPTS_VALUE)
is_ref_pkt = can_split = 0;
if (is_ref_pkt)
hls->duration = (double)(pkt->pts - hls->end_pts)
* st->time_base.num / st->time_base.den;
if (can_split && av_compare_ts(pkt->pts - hls->start_pts, st->time_base,
end_pts, AV_TIME_BASE_Q) >= 0) {
int64_t new_start_pos;
av_write_frame(oc, NULL); /* Flush any buffered data */
new_start_pos = avio_tell(hls->avf->pb);
hls->size = new_start_pos - hls->start_pos;
ret = hls_append_segment(hls, hls->duration, hls->start_pos, hls->size);
hls->start_pos = new_start_pos;
if (ret < 0)
return ret;
hls->end_pts = pkt->pts;
hls->duration = 0;
if (hls->flags & HLS_SINGLE_FILE) {
if (hls->avf->oformat->priv_class && hls->avf->priv_data)
av_opt_set(hls->avf->priv_data, "mpegts_flags", "resend_headers", 0);
hls->number++;
} else {
avio_closep(&oc->pb);
ret = hls_start(s);
}
if (ret < 0)
return ret;
oc = hls->avf;
if ((ret = hls_window(s, 0)) < 0)
return ret;
}
ret = ff_write_chained(oc, pkt->stream_index, pkt, s, 0);
return ret;
}
static int hls_write_trailer(struct AVFormatContext *s)
{
HLSContext *hls = s->priv_data;
AVFormatContext *oc = hls->avf;
av_write_trailer(oc);
if (oc->pb) {
hls->size = avio_tell(hls->avf->pb) - hls->start_pos;
avio_closep(&oc->pb);
hls_append_segment(hls, hls->duration, hls->start_pos, hls->size);
}
av_freep(&hls->basename);
avformat_free_context(oc);
hls->avf = NULL;
hls_window(s, 1);
hls_free_segments(hls->segments);
hls_free_segments(hls->old_segments);
return 0;
}
#define OFFSET(x) offsetof(HLSContext, x)
#define E AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{"start_number", "set first number in the sequence", OFFSET(start_sequence),AV_OPT_TYPE_INT64, {.i64 = 0}, 0, INT64_MAX, E},
{"hls_time", "set segment length in seconds", OFFSET(time), AV_OPT_TYPE_FLOAT, {.dbl = 2}, 0, FLT_MAX, E},
{"hls_list_size", "set maximum number of playlist entries", OFFSET(max_nb_segments), AV_OPT_TYPE_INT, {.i64 = 5}, 0, INT_MAX, E},
{"hls_ts_options","set hls mpegts list of options for the container format used for hls", OFFSET(format_options_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
{"hls_wrap", "set number after which the index wraps", OFFSET(wrap), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, E},
{"hls_allow_cache", "explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments", OFFSET(allowcache), AV_OPT_TYPE_INT, {.i64 = -1}, INT_MIN, INT_MAX, E},
{"hls_base_url", "url to prepend to each playlist entry", OFFSET(baseurl), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
{"hls_segment_filename", "filename template for segment files", OFFSET(segment_filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
{"hls_key_info_file", "file with key URI and key file path", OFFSET(key_info_file), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
{"hls_flags", "set flags affecting HLS playlist and media file generation", OFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0 }, 0, UINT_MAX, E, "flags"},
{"single_file", "generate a single media file indexed with byte ranges", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_SINGLE_FILE }, 0, UINT_MAX, E, "flags"},
{"delete_segments", "delete segment files that are no longer part of the playlist", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_DELETE_SEGMENTS }, 0, UINT_MAX, E, "flags"},
{"round_durations", "round durations in m3u8 to whole numbers", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_ROUND_DURATIONS }, 0, UINT_MAX, E, "flags"},
{"discont_start", "start the playlist with a discontinuity tag", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_DISCONT_START }, 0, UINT_MAX, E, "flags"},
{"omit_endlist", "Do not append an endlist when ending stream", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_OMIT_ENDLIST }, 0, UINT_MAX, E, "flags"},
{ NULL },
};
static const AVClass hls_class = {
.class_name = "hls muxer",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVOutputFormat ff_hls_muxer = {
.name = "hls",
.long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),
.extensions = "m3u8",
.priv_data_size = sizeof(HLSContext),
.audio_codec = AV_CODEC_ID_AAC,
.video_codec = AV_CODEC_ID_H264,
.flags = AVFMT_NOFILE | AVFMT_ALLOW_FLUSH,
.write_header = hls_write_header,
.write_packet = hls_write_packet,
.write_trailer = hls_write_trailer,
.priv_class = &hls_class,
};